Device for barking of logs or the like



1952 N. ALFSEN DEVICE FOR BARKING OF LOGS OR THE LIKE 2 SHEETS-SHEET 1 Filed July 30, 1947 Jan. 8, 1952 ALF-SEN 2,581,617

DEVICE FQR BARKING OF LOGS OR THE LIKE Filed July 30; 1947 2 SPEETS SI-IEET 2 Patented Jan. 8, 1952 DEVICE FOR BARKING OF LOGS OR THE LIKE! Nikolai Alfsen, Oslo, Norway Application July 30, 1947, serial No. 764,675 In Norway February 14, 1947 Claims.

The present invention relates to a device for barking of logs, log-ends and the like. The device is particularly suitable for pre-barking the logs prior to the final finishing barking in abarking drum, but it is meant to be able to peel off the bark so effectively that a finishing barking eventually will be superfluous.

The object of the invention is to provide a barking machine with means to simultaneously rotate and scrape a log, said means comprising two cooperating coplanar peeling-wheels, which rotate in the same direction but at different peripheral speeds, so that, at least between one of the wheels and the log, there will be a sliding effect, causing the wheel concerned to scrape the log and thereby peel oil the bark; and with means to simultaneously score the bark and axially advance the log, said means comprising .an idler wheel having a helical knife formed on its periphery, so that the incisions made in the bark by said knife are of helical shape, the log thereby being axially displaced and the barking of the log thereby being initiated.

Other characteristic features of the invention are disclosed below.

The invention is illustrated by way of example in the accompanying diagrammaticai drawing.

Figure 1 is a sectional end view of a preferred embodiment of the device, and is taken on the line I--I in Figure 2, and

Figure 2 is a sectional side view, and is taken on the line 11-11 in Figure 1.

Figures 3 and 4 show an alternative embodiment of the invention in end-view and plan-view respectively.

The barking members of the device shown in Figures 1 and 2 comprise two toothed wheels 2 and 3 having parallelly mounted shafts and being situated opposite each other at such a relative distance that they do not engage each other. The bearings of the toothed wheels 4 and .5 are mounted on a stand I, to which are fastened two brackets l6 and I1 serving the purposes mentioned below. By means of a driving device (not shown) the toothed wheels are both rotated in the same direction (indicated on the drawing in Figure l by arrows) but with different peripheral speed. In the example shown the toothed wheel 3 is presupposed to have the greater peripheral speed. The teeth 2 and 3 of the wheels are suitably formed, but do not necessarily have sharp cutting-edges The log 9, which is to be barked, is, as shown on the drawing, placed axially above the wheels 2 the direction indicated by the arrow in Fig.

2 and 3 in the space provided between them, in such a way that it rests on the teeth 2' and 3' of the wheels. In front of and behind the wheels the log is guided in suitably shaped guiding members 6 and i, each carried by a sawbuck-shaped stand 8 or the like. During the rotation of the wheels the log will be rotated in owing to the friction arising between the log and the teeth 2' and 3'. However, because the wheels are rotating with difierent peripheral speeds, there will always be a sliding effect, at least between the log and the teeth of one of the wheels. Due to said sliding movement the teeth, being shaped suitably to the p pose, have a scraping and thereby also a peeling effect on the log. If the log is rotating with a peripheral speed equal to that of the wheel 3, which has the greater speed, the teeth 2- of the other wheel will have a sliding motion relatively to the surface of the log and thereby cause the bark to be peeled off. Similarly the teeth 3 will slide on the surface of the log and have a peeling effect, if the log is rotating with the same peripheral speed as the wheel '2. If the rotating speed of the log lies somewhere between these two extremes, the teeth of both wheels cause the bark to be peeled off.

in order to obtain a thorough peeling effect it is necessary that the log be pressed against the wheels with a suitable pressure and the log must be fed longitudinally as shown by the arrow in Figure 2. This is obtained by means of one or more helical-shaped knives II provided on the circumference of an idler wheel II], which is rotatably mounted in bearings l2 provided on the under side of an arm I 3 swingable in the vertical plane. The idler wheel is placed a little behind the wheels 2, 3 with reference to the feeding direction of the log, the shaft of the idler wheel bein parallel or almost parallel to the log. By means of a pivot M the arm Is at one end is swi'ngably attached to an upper portion l5 of the bracket It. The opposite end of the arm 13 is under the pressure of a spring 18 which tends to swing the arm [3 in a downward direction, so that the wheel ID with the knife II is pressed against the log 9 with a certain pressure. The

free end of the arm I 3 is guided by the bracket l l in such a way that it cannot move transversely.

When the knife H is pressed against the log 9 while said log is rotating, there will be cut helically shaped incisions in the bark as shown in Figure 2, with the result that the bark will be removed more easily by the teeth of the peeling.

wheels. At the same time, the motion of the knife will cause the log, while being rotated, to be fed in the longitudinal direction as shown by the arrow in Figure 2, said knife, when in engagement with the log, on account of its helical form, tending to move axially along the log in the opposite direction. As axial movement of the knife is out of the question, the log will be forced to move axially in the direction indicated by said arrow, The outer surface of the wheel will limit the depth of the incisions made in the log by the knife.

In order to remove possibly remaining bark, a scraping-knife i9 is provided in front of the peeling-wheels with reference to the feeding direction of the log, said scraping-knife being suitably attached swingably to an arm 20 or the like. The edge of this scraping-knife is suitably situated at an angle of for instance 45 relative to the longitudinaldirection of the log. The scraping-knife may be adjustable in such a way that it touches the surface of the log after the greater part of the bark has been peeled off, and preferably is mounted in a resilient manner, so that it may follow inequalities in the log. It will be seen from Figure 2 how the barking proceeds. The principal part of the peeling process is carried out where the log is acted upon by the feeding-knife and the peeling-wheels, and this part of the log, after such preliminary barking, is shown by way of indication between the peeling-wheels and the scraping-knife, while that portion of the log, which has been more completely peeled by the scraping-knife, is shown to the left of the partially barked portion.

According to the embodiment shown in Figures 3'and 4 there are provided two wheels 2| and 22 placed just behind the peeling-wheels 2 and 3 and co-axial with the same. The purpose of the wheels 2| and 22, which are driven independently of the peeling-wheels and with peripheral speeds equal to each other, is only to ensure an even rotation of the log.

One of the peeling-wheels, in this case the wheel 2, is mounted displaceably in the transverse direction of the log, so that it may be pressed against the log with greater or less force according to wish. The mechanism for effecting this displacement may consist of an angle lever 23, 25

mounted on a pivot 24. The lever 25 is by means of a pivot 26 jointed to a bar 21, the opposite end of which by means of a pivot 28 is connected to the peeling-wheel bearing, which is displaceably mounted in a suitable guide. Thus the pressure of the wheel 2 against the log may be varied by operating the lever handle 23.

I claim:

1. A log debarking device comprising in combination a frame; two stationary guide members for the entrance and exit of a log to be debarked, said guide members being arranged in alignment in said frame along the path of log travel and being separated from each other by a gap; a pair of toothed wheels spaced from each other in a common plane lying normal to said path of log travel and protruding into said gap between said guide members, said pair of toothed wheels being connected to the frame for rotation about parallel axes in the same peripheral direction; means to rotate said toothed wheels at different peripheral speeds; an idler wheel mounted .in said frame above the gap between said guide members in a plane parallel to, but spaced from said common plane, and being rotatable about an axis parallel to the axes of said toothed wheels; at least one helically shaped knife arranged on the periphery of said idler wheel; and means for pressing said idler wheel and said helically shaped knife against the log to be debarked, whereby said helically shaped knife makes a helical incision into the bark of the log. thus facilitating the removal of the bark by said toothed wheel, and at the same time feeds the log to be debarked in the longitudinal direction thereof.

2. A device as claimed in-claim 1, said helically shaped knife having two turns so as to make a pair of parallel incisions in the log to be debarked.

3. A device as claimed in claim 1, the plane of said idler wheel being spaced from said common plane toward the entrance side of the frame.

4. A device as claimed in claim 1, and a lever pivotally connected to said frame and arranged above said toothed wheels; bearings for said idler wheel, said bearings being rigidly connected to the said lever; and resilient means for swinging said lever about the pivot thereof so as to press said idler wheel and said helically shaped knife against the log to be debarked.

5. A device as claimed in claim 1, and a bearing for the axle of one of said toothed wheels; and means for displacing said bearing in a direction substantially parallel to the common plane of said toothed wheels so as to change the distance between the latter.

NIKOLAI ALFSEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 896,851 McCarren Aug. 25, 1908 1,082,544 Matheus Dec. 30, 1913 1,388,309 Ross Aug. 23, 1921 1,521,735 Vlahos Jan. 6, 1925 1,588,772 Rorabeck June 15, 1926 2,012,716 Colchensky Aug. 27, 1935 2,027,173 Jackson et al Jan. 7, 1936 2,044,561 Bidle June 16, 1936 2,055,108 Hokonson Sept. 22, 1936 2,338,136 Shaw et a1 Jan. 4, 1944 2,341,640 Melhorn Feb. 15, 1944 FOREIGN PATENTS Number Country I Date 358,636 Germany Sept. 15, 1922 76,235 Sweden Jan. 10, 1933 

